Insulin/IGF-1 Signaling Regulates Proteasome Activity through the Deubiquitinating Enzyme UBH-4

Autor: Olli Matilainen, Leena Arpalahti, Ville Rantanen, Sampsa Hautaniemi, Carina I. Holmberg
Jazyk: angličtina
Rok vydání: 2013
Předmět:
Zdroj: Cell Reports, Vol 3, Iss 6, Pp 1980-1995 (2013)
Druh dokumentu: article
ISSN: 2211-1247
DOI: 10.1016/j.celrep.2013.05.012
Popis: The proteasome plays an important role in proteostasis by carrying out controlled protein degradation in the cell. Impairments in proteasome function are associated with severe and often age-related diseases. Here, we have characterized a molecular mechanism linking insulin/IGF-1 signaling (IIS) to proteasome activity. We show that decreased IIS, which promotes proteostasis and longevity, increases proteasome activity through the FOXO transcription factor DAF-16 in C. elegans. Furthermore, we reveal that DAF-16 represses expression of the proteasome-associated deubiquitinating enzyme ubh-4, which we suggest functions as a tissue-specific proteasome inhibitor. Finally, we demonstrate that proteasome activation through downregulation of the ubh-4 human ortholog uchl5 increases degradation of proteotoxic proteins in mammalian cells. In conclusion, we have established a mechanism by which the evolutionarily conserved IIS contributes to the regulation of proteasome activity in a multicellular organism.
Databáze: Directory of Open Access Journals